Main Difference
The main difference between Arabic and Urdu is that the Arabic is a Semitic language and Urdu is a language in Pakistan
Arabic
Arabic (Arabic: اَلْعَرَبِيَّةُ, al-ʿarabiyyah, [al ʕaraˈbijːa] (listen) or عَرَبِيّ, ʿarabīy, [ˈʕarabiː] (listen) or [ʕaraˈbij]) is a Semitic language that first emerged in the 1st to 4th centuries CE. It is now the lingua franca of the Arab world. It is named after the Arabs, a term initially used to describe peoples living in the area bounded by Mesopotamia in the east and the Anti-Lebanon mountains in the west, in Northwestern Arabia and in the Sinai Peninsula. The ISO assigns language codes to thirty varieties of Arabic, including its standard form, Modern Standard Arabic, also referred to as Literary Arabic, which is modernized Classical Arabic. This distinction exists primarily among Western linguists; Arabic speakers themselves generally do not distinguish between Modern Standard Arabic and Classical Arabic, but rather refer to both as al-ʿarabiyyatu l-fuṣḥā (اَلعَرَبِيَّةُ ٱلْفُصْحَىٰ, “the purest Arabic”) or simply al-fuṣḥā (اَلْفُصْحَىٰ).
Arabic is widely taught in schools and universities and is used to varying degrees in workplaces, government and the media. Arabic, in its standard form, is the official language of 26 states, as well as the liturgical language of the religion of Islam, since the Quran and Hadith were written in Arabic.
During the Middle Ages, Arabic was a major vehicle of culture in Europe, especially in science, mathematics and philosophy. As a result, many European languages have also borrowed many words from it. Arabic influence, mainly in vocabulary, is seen in European languages—mainly Spanish and to a lesser extent Portuguese and Catalan—owing to both the proximity of Christian European and Muslim Arab civilizations and almost 800 years of Arabic culture and language presence in the Iberian Peninsula, referred to in Arabic as al-Andalus. Sicilian has about 500 Arabic words, many of which relate to agriculture and related activities, as a legacy of the Emirate of Sicily from the mid-9th to mid-10th centuries, while Maltese language is a Semitic language developed from a dialect of Arabic and written in the Latin alphabet. The Balkan languages, including Greek and Bulgarian, have also acquired a significant number of Arabic words through contact with Ottoman Turkish.
Arabic has influenced many other languages around the globe throughout its history. Some of the most influenced languages are Persian, Turkish, Azeri, Armenian, Hindustani (Hindi and Urdu), Kashmiri, Kurdish, Bosnian, Kazakh, Bengali, Malay (Indonesian and Malaysian), Maldivian, Pashto, Punjabi, Spanish, Tagalog, Assamese, Sindhi, Odia and Hausa and some languages in parts of Africa. Conversely, Arabic has borrowed words from other languages, including Hebrew, Greek, Aramaic, and Persian in medieval times and languages such as English and French in modern times.
Arabic is the liturgical language of 1.8 billion Muslims and Arabic is one of six official languages of the United Nations. All varieties of Arabic combined are spoken by perhaps as many as 422 million speakers (native and non-native) in the Arab world, making it the fifth most spoken language in the world. Arabic is written with the Arabic alphabet, which is an abjad script and is written from right to left, although the spoken varieties are sometimes written in ASCII Latin from left to right with no standardized orthography.
Urdu
Urdu (; Urdu: اُردُو ALA-LC: Urdū [ˈʊrduː] (listen)) (also known as Lashkari, locally written لشکری [lʌʃkɜ:i:])—or, more precisely, Modern Standard Urdu—is a Persianised standard register of the Hindustani language. It is the official national language and lingua franca of Pakistan. In India, it is one of the 22 official languages recognized in the Constitution of India, having official status in the six states of Jammu and Kashmir, Telangana, Uttar Pradesh, Bihar, Jharkhand and West Bengal, as well as the national capital territory of Delhi.
Apart from specialized vocabulary, spoken Urdu is mutually intelligible with standard Hindi, another recognized register of Hindustani. The Urdu variant of Hindustani received recognition and patronage under British rule when the British replaced the local official languages with English and Hindustani written in Nastaʿlīq script, as the official language in North and Northwestern India. Religious, social, and political factors pushed for a distinction between Urdu and Hindi in India, leading to the Hindi–Urdu controversy.According to Nationalencyklopedin’s 2010 estimates, Urdu is the 21st most spoken first language in the world, with approximately 66 million speakers. According to Ethnologue’s 2017 estimates, Urdu, along with standard Hindi and the languages of the Hindi belt (as Hindustani), is the 3rd most spoken language in the world, with approximately 329.1 million native speakers, and 697.4 million total speakers.